CVE-2026-93271

What the bug is

ath11k can receive HT/VHT/HE frames whose reported MCS is above the maximum that can be expressed in the corresponding mac80211 rate space (e.g. an HE frame reported with MCS 12, while HE tops out at MCS 11). The frame itself is valid and decodes correctly, but for such a frame ath11k_dp_rx_h_rate() leaves rx_status->rate_idx set to the out-of-range value and never assigns rx_status->encoding, so it stays RX_ENC_LEGACY from the ath11k_dp_rx_h_ppdu() initialization. Once that frame reaches mac80211 it trips the rate sanity check and the frame is dropped with a splat: ath11k_pci 0000:03:00.0: Received with invalid mcs in HE mode 12 WARNING: CPU: 0 PID: 0 at net/mac80211/rx.c:5433 ieee80211_rx_list+0xb0a/0xe90 [mac80211] Dropping the frame would discard otherwise valid data, so instead cap the reported MCS to the maximum the rate space can express and deliver the frame. Set rx_status->encoding before the range check and assign rate_idx from the capped value, so a frame with an out-of-range MCS no longer leaves partial or bogus rate metadata behind. Also downgrade the logging level since they are not treated as invalid frames now. The only loss is that such a frame is reported as the capped MCS in the rx rate statistics. Tested-on: WCN6855 hw2.1 PCI WLAN.HSP.1.1-03125-QCAHSPSWPL_V1_V2_SILICONZ_LITE-3.6510.41

Where it lives

The fix touches these files. If the subsystem is one you do not use, the practical exposure is lower, though the package is still the vulnerable one.

drivers/net/wireless/ath/ath11k/dp_rx.c

What this is

QUALCOMM ATHEROS ATH11K WIRELESS DRIVERMAINTAINERS section matched on drivers/net/wireless/ath/ath11k/ · linux-wireless@vger.kernel.org · Supported

Kernel module

ath11k

Check it on the machine

grep -wE 'CONFIG_ATH11K|CONFIG_WLAN|CONFIG_WLAN_VENDOR_ATH' /boot/config-$(uname -r)

Reads the booted kernel's own configuration, on the machine and nowhere else. =y is built in, =m is a module, and an is not set line means the code is not there.

lsmod | grep -w ath11k

Prints a line if that module is loaded right now, and nothing if it is not. One that is not loaded can still be loaded later by anything that needs it.

Show whether Debian builds this, per release

Debian builds this, but not on every flavour. At least one release below builds the code on some of its kernel flavours and not on others, so the answer depends on the architecture and flavour installed.

• bookwormMnot built on amd64/cloud-amd64, arm64/cloud-arm64
• trixie, forky, sidMnot built on amd64/cloud-amd64, arm64/cloud-arm64, s390x/s390x
• bookworm · linux-6.12Mnot built on amd64/cloud-amd64, arm64/cloud-arm64

M

a module where it is built at all; some flavours do not build it

Build switches

CONFIG_ATH11K, CONFIG_WLAN, CONFIG_WLAN_VENDOR_ATH

Reads as

all on means the file is compiled; any one off means it is not.

From the configuration Debian publishes for every kernel flavour it builds. It covers only the architectures Debian ships a linux-config package for, and nothing about a kernel you built yourself. Debian's own status above stays authoritative about the source package.MAINTAINERS kbuild Makefiles Debian linux-config packages

Signals

Published

2026-09-24 (24 days ago)source

CVSS

no vector published, unrated

Attack vector

not published

EPSS

0.20%, higher than 8.7% of all CVEssource

CISA KEV

not listedthe KEV catalogue

Debian urgency

not yet assignedsource

Subsystem

drivers/net

Upstream fixes

The versions the CNA records as introducing and fixing this, and the commit for each. source

Introduced	Fixed in	Commit
5.6	5.10.270	6ad04c3e2ec5
5.6	5.15.221	a6b951f79e66
5.6	6.1.188	b77bfe6e59b9
5.6	6.6.157	fb7b9a7209f8
5.6	6.12.110	a0b3e6f9645d
5.6	6.18.52	2bb2a778a487
5.6	7.2.6	ccbd20f2168f
5.6	7.3	12b09e478aa7

Debian advisories